Retrievable packer



Jan. 7, 1969 M. B. CONRAD 3,420,307

RETRIEVABLE PACKER INVENTOR. f? Amer/N CoA/@40 BY ,QQW

Jan. 7, 1969 M. B. CONRAD 3,420,307

RETRI EVABLE PACKER Jan. 7, 1969 M. Bf CONRAD 3,420,307

RETRIEVABLE PACKER United States Patent O 3,420,307 RETRIEVABLE PACKER Martin B. Conrad, Carpinteria, Calif., assignor to Baker Oil Tools, Inc., City of Commerce, Calif., a corporation of California Filed Nov. 14, 1966, Ser. No. 593,921

U.S. Cl. 166-134 21 Claims nt. Cl. E21b 23/00 ABSTRACT F THE DISCLOSURE A retrievable double holding well packer, the resilient packing means of which is held in compression upon setting of the upwardly and downwardly holding slips by Ian assemblage delining a chamber containing a quantity of granular material, the assembly including a shiftable closure for the chamber, so that the chamber may be opened to dump the granular material and thereby relieve the compressive force on the resilient packing means.

This invention pertains to a packer for use in wells.

The packer of this invention is of the retrievable type, so that it can be released and removed from the well when desired. The packer is both set and released by mechanical means and in the packed-olf condition is capable of withstanding Very high pressures. Release is complete, so that the tool is moved in the well without diliculty in the retrieval operation.

In general, the packer of this invention includes an elongated mandrel around which is at least one resilient collar placed between opposed shoulders. Slips are provided outwardly of the shoulders and lock against the wall of the well when the resilient collar is compressed as the tool is packed olf. The force between one set of slips and the shoulder at one end of the collar is transmitted through a compression element made up of telescoping sleeves. These sleeves define an annular chamber within which is a particulate material, such as sand. When the tool is to be released, one of the sleeves is shifted in position so that the chamber is opened and the sand is dumped. When this occurs, the compression element can no longer resist the force upon it, and the shoulders thereby release the resilient collar. The mandrel is segmented, allowing one section to be disconnected from the remainder. This segment includes a shoulder for sliding the sleeve element to dump the sand and effect the release of the resilient collar. The mandrel also includes a shoulder for releasing one set of the slips, so that the tool is no longer held in the well casing and can be removed readily./

One important advantage of the design of this invention is that it avoids the use of auxiliary seals in the packer assembly. The only sealing elements present are those provided by the packing elements.

An object of this invention is to provide an improved retrievable well packer.

Another object of this invention is to provide a packer that can be released completely and Without diiculty, permitting it to be moved easily within a well.

A further object of this invention is to provide a packer that is securely held in the packed-oli condition, and will resist high pressure differentials, yet can be released at will.

Another object of this invention is to provide a packer that incorporate no seals other than those provided by the packing elements.

A still further object of this invention is to provide a device to be positioned within a well in which a resilient member is held in a compressed condition through a compression element that can be selectively made incapable of resisting the forces upon it for releasing the resilient member.

Patented Jan. '7, 1969 ice Yet another object of this invention is to provide a well tool in which a compression force is transmitted through a particulate material, with provision for dumping the particulate .material to relieve the compression force.

A still further object of this invention is to provide a Well packer that is simple and economical to construct and operate.

These and other objects will become apparent from the following detailed description taken in connection with the accompanying drawing in which:

FIGURES 1a and 1b provide a longitudinal sectional view of the tool of this invention 'as it is being run into a well, with FIGURE 1a illustrating the upper portion of the tool and FIGURE 1b the lower portion;

FIGURE 2 is an enlarged transverse sectional view taken along line 2-2 of FIGURE 1b;

FIGURES 3a and 3b 4are views -similar to FIGURES la and lb, illustrating the tool in the packed-off condition; 'and FIGURES 4a and 4b are views similar to FIGURES 1a land 1b, showing the tool `after release when it is ready for retrieval.

With reference to FIGURES la and 1b, the packer of this invention includes an elongated tubular mandrel 10 provided with exterior teeth 11 at its upper end by which it is adapted for coupling to a tubing string for movement within a well casing 12. Beneath the teeth 11 is a drag means 14, which provides a resistance to movement of the tool in the well casing. The drag means may be similar to that illustrated in Patent 3,135,329. Brielly, this includes a tubular housing 15 connected to the exterior of the mandrel 10 for controlled release of the housing 15 for longitudinal movement of the mandrel 10 relative to the housing 15. In the illustrative embodiment, the releasable or control means includes an external thread 10a on the mandrel and a mating thread 15a in the housing 15, although other coventional control means may be employed. In `any event, the housing 15 is provided with a plurality of longitudinally extending slots 16 spaced circumferentially around the member 15. Within the slots 16 are drag blocks 17, which are biased outwardly in the radial direction `by compression springs 18 and 19. The springs cause the drag blocks to be'ar against the inner surface of the casing 12 to provide `a yieldable resistance to the movement of the tool longitudinally within the casing. Flanges 20 and 21 overlap the drag blocks at the slots 16, so that the drag blocks are retained when the tool is removed from the well casing.

Below the friction means 14 is a slip assembly 23, which also may be similar to the corresponding item illustrated in Patent 3,135,329. The individual slip elements 24 are retained by a ring 25 which, in turn, is coupled to the tubular housing 15 by a split ring 26. The latter element has an annular recess in its inner surface that receives flanges 27 and 28 of the tubular housing 15 and the ring 25, respectively, in effecting the connection between the members 15 and 25.

The slip elements 24 are T-shaped at one end, each having a base portion 29 received in an upwardly 'and outwardly inclined slot 30 in the ring 25. At the opposite end, the slips include teeth 31 facing the wall of the casing, beneath which are downwardly sloping surfaces 32 adacent similarly inclined expander surfaces 33 forming the walls of longitudinally etxending recesses 34 in the upper end of a tubular member 35. Along the sides of the slips 24 are ribs 35 that lit within complementary slots 37 in the member 35 at the recesses 34.

The lower end of the tubular member 35 connects by threads to a sleeve 38 which is of thinner wall than the member 35, but has the same outer diameter. The bottom end of the sleeve 38 overlaps an additional sleeve element 39, and the members 38 and 39 are provided with inward- 1y and outwardly extending shoulders 40 and 41, respectively, which retain the sleeves 38 and 39 against axial outward movement of one relative to the other.

The bottom end of the tubular member 35 and the upper end of the sleeve 39 overlap the upper and lower ends, respectively, of a short sleeve 42 which circumscribes the periphery of the mandrel and is spaced inwardly of the sleeve 38. The result is an annular chamber, with the sleeve 38 providing the outer wall and the sleeve 42 the inner wall. The shoulder formed by the end of the member 35, which upon assembly in integral with the outer sleeve 38, delines the 4upper end wall of the chamber, while the corresponding shoulder at the end of the sleeve 39 acts as the lower wall. This chamber is lled with a particulate material 43, such as sand. The sand 43 prevents the sleeve 39 from telescoping upwardly into the sleeve 38, holding the sleeves extended relative to each other with the abutments 40 and 41 in adjacency.

The lower end of the sleeve 39, as seen in FIGURE 1b, is threaded onto the upper end of a tubular element 45 at the bottom end of which is an outwardly projecting shoulder portion 46. The latter section is above a series of three resilient elastomeric collars 47, 48 and 49 which circumscribe the mandrel 10 and serve as the packing elements. A washer 50 is interposed between the packing elements 47 and 48, and a similar washer 51 is located between the packing elements 48 and 49.

Inwardly of the tubular member 45, the mandrel 10 is recessed to receive a small ring 52 that projects beyond the circumference of the mandrel to define an upwardly facing shoulder 53. A similar ring 54 is located above the ring 52 adjacent the upper end of the tubular member 35, providing a shoulder 55.

The mandrel 10 is in three sections, including an upper portion 57 connected by threads to a central section 58 inwardly of the tubular memebr 45. The lower end of the central mandrel portion 58 threads 57a and 57b into the bottom mandrel section 59, which is provided with an outwardly extending flange 60 at the lower end of the tool. Above the flange 60 and spaced from it is a slip assembly 61, which corresponds generally to the slip assembly 23 at the upper portion of the tool. The slip assembly 61 includes a ring 62 provided with inclined slots 63 that receive the base portions 64 of the individual slip elements 65. The ring 62 is positioned relative to the mandrel 10 by means of a set screw 66 that extends through an opening in a resilient split ring 67 to bear against the surface of the lower mandrel portion 59. The ring 67 is received in an annular recess 68 in the mandrel and projects above the surface of the mandrel, providing a shoulder 69 that is engaged by a complementary portion of the ring 62 that circumscribes it. The ring 67 is compressed in the position of FIGURE 1b where it is held in the annular recess 68 by the ring 62. In its free position, the ring 67 assumes a larger diameter than that of the recess that receives it.

The upper ends of the slip elements 65, the outer portions of which are provided with teeth 70, bear against the tapered expander surfaces 71 of a tubular member 72, the upper end 73 of which forms a shoulder that engages the bottom resilient packing element 49. A shear screw 74 extends through the member 72 to a recess in the surface of the mandrel, thereby axially positioning the member 72 relative to the mandrel. In addition, the mandrel and member 72 are coupled for simultaneous rotational movement through the provision of akey 75 that extends from a keyway 76 in the member 72 into a keyway 77 in the periphery of the mandrel (see FIGURE 2).

The packer of this invention is run into the well casing 12 with the parts in the relationship illustrated in FIG- URES la and 1b. Only the drag blocks 17 contact the surface of the casing, while all other portions of the tool are recessed beneath the periphery of the drag blocks and offer no resistance to movement of the packer.

When the desired location is reached, the tool is packed olf to the position illustrated in FIGURES 3a and 3b. To

accomplish this, the mandrel assembly 10 first is rotated, which unscrews the connection at the upper end of the tool between the mandrel 10 and the tubular housing 15. This occurs because the drag blocks 17, bearing against the wall of the casing 12, frictionally resist rotation and hold the tubular housing 15 motionless while the mandrel turns. After the threads have been separated at the tubular housing 15, an upward pull is exerted on the mandrel 10. This force is transmitted through the shoulder 69 of the split ring 67 to the ring 62 of the lower slip assembly 61, thereby causing the ring 62 and the slip elements 65 to move upwardly with the mandrel 10. The tubular slip expander member 72 is caused to move correspondingly upwardly by the screw 74 connecting the member 72 to the mandrel 10. From the tubular member 72, the upward force is transmitted through the resilient packing elements 47, 48 and 49, to the tubular member 45 above the packing elements. From there, the force is transmitted through the sleeve 39 and the sand 43 into the member 35 and thence to the upper slip assembly 23.

Because of the resistance to axial movement relative to the well casing afforded by the friction means 14 and its drag blocks 17, the slip elements 24 are moved outwardly by being slid along the inclined surfaces 33 of the tubular member 35. This brings the teeth 31 into engagement with the inner wall of the casing 12, as seen in FIGURE 3a. Also, the resilient packing elements 47 48 and 49 are compressed between the shoulder portion 46 of the member 45 and the upper end 73 of the tubular member 72 beneath them so that they are squeezed outwardly, as seen in FIGURE 3b, to firmly engage the wall of the casing 12 and form a tight seal therewith.

The force pulling on the mandrel 10 causes the screw 74 to shear as the slips 24 become set and a resistance is generated to upward movement. The compression from above the member 72 as the slips 24 lock against the casing results in the shearing of the screw 74. This allows movement of the mandrel 10 upwardly relative to the member 72 so that the lower slips 65 are cammed outwardly by the Surfaces 71 to likewise become set. This holds the member 72 in a fixed position relative to the casing with the packing elements 47, 48 and 49 cornpressed between the shoulders 46 and 73. The slips 24 and 65 hold against upward and downward movement, respectively, so that the tool remains packed off in the condition of FIGURES 3a and 3b after the upward pull `on the mandrel 10 is released. It can be left in this condition indefinitely without further attention.

With the tool packed oli, therefore, a compressive force is transmitted inwardly from the slips to the opposite ends of the assembled packing elements. At the upper end, the assembled sleeves 45 and 39, the short inner sleeve 42, the outer sleeve 38 and its connected member 35, together with the sand 43, act as a unitary rigid compression element that transfers the force to the packing collars. The particulate material 43, confined in the annular chamber, readily withstands the compressive forces imposed upon it.

When it comes time to retrieve the packer, the first step is to sit down on the mandrel, which shears the screw 66 that extends through the ring 62 into the ring 67 and connects the ring 62 to the mandrel. This screw shears because, when a downward force is imposed upon the mandrel, the lower slip assembly 61 holds the ring 62 against movement in that direction. The entire downward force, therefore, is imposed on the screw 66 to shear it. The mandrel is moved downwardly upon the shearing of the screw 66 to a position where the split ring 67 no longer is held in the recess 68 in the mandrel. This movement of the mandrel shifts the split ring 67 with it until the ring 67 reaches the clearance space 78 provided at the lower end of the member 62. Therefore, the split ring 67 springs out of the annular recess 68 that has retained it and no longer presents its shoulder 69 adjacent the cooperating shoulder of the member 62.

After the screw 66 has been sheared and the mandrel shifted downwardly, the mandrel is rotated, which unscrews the threaded connection 57a, 57b between the upper portion 57 of the mandrel and the intermediate portion 58. The threads 57a, 57b can be separated because the intermediate portion 58 of the mandrel is coupled to the tubular member 72 through the key 75. The member 72, in turn, is prevented from rotation by the slips. Therefore, the central section 58 of the mandrel is `held motionless as the upper part 57 is rotated.

After the threads between the sections 57 and 58 of the mandrel have been disconnected, an upward pull is exerted on the mandrel. This initially moves only the upper section 57, because the remainder of the mandrel at that time is retained with the portions of the tool that are locked against the casing. As the upward movement of the upper mandrel section 57 takes place, the shoulder 53 provided .by the annular ring 52 moves upwardly to engage the lower end of the sleeve 42. Assurance against hydraulic lock is afforded by a bleed opening 79 through the tubular member `45. Continued upward movement of the mandrel section 57 causes the shoulder 53 of the ring 52 to slide the sleeve 42 upwardly with the mandrel. This removes the inner wall of the chamber that receives the sand 43. Consequently, the sand 43 is dumped into the interior of the tool and out through the bore in the mandrel. With the sand discharged, there is no further resistance to t-he compressive forces that formerly were transmitted through the sand to the packing elements. Relative movement may then take place between the sleeves 39 and 38 as the former is free to slide into the latter. This occurs as the packing elements 47, 48 and 49 return to their free dimensions upon thereby being relieved of the compression upon them. In other words, as soon as the sand 43 is dumped, the retaining force on the packing elements is released. Therefore, the resilient packing elements resume their original contour, and no longer are squeezed outwardly against the wall of the well casing.

Continued upward movement of the upper section 57 of the mandrel then :brings the shoulder 55 of the ring 54 into engagement with an inwardly extending shoulder 80 at the upper part of the tubular housing 15. When the member 54 engages the shoulder 80, an upward pull is exerted through the tubular member to t-he slipholding ring 25, which, in turn, pulls on the backs of the slip elements 24. Therefore, the slip elements 24 are released, and the slip assembly 23 provides no further resistance to the movement of the packer in the well casing 12. The shoulders 40 and 41 of the sleeves 38 and 39, respectively, are brought into engagement as the mandrel is pulled upwardly. Similarly, an inwardly extending shoulder 81 on the member 45 contacts an outwardly projecting shoulder 82 on the intermediate mandrel section 58. The lower portion of the tool then is caused to move with the upper part which previously had been unthreaded from it so that the tool can :be removed as a unit. With the sholder 69 of the split ring 67 no longer obstructing downward movement of the slip-holding ring 62, the lower slip elements 65 are free to move toward the end flange 60 of the mandrel as the release of the tool is completed. All the resisting force of the slips and the packers is removed and the tool in its entirety is pulled from the well without difliculty.

Sand is especially well suited for the material to be used in conjunction with the compression element of the tool of this invention because it withstands high compressive forces, yet will dump easily when released. Also, it is of low cost and readily available. However, particles or segments of other materials may be used so long as they will stand up under the load and subsequently can be ejected the chamber. The substance in the chamber may be unitary loriginally and assume a particulate form after being subjected to loads so that it then can be dumped in retrieving the tool. An example of the latter is sand initially Iheld together with a light binder, such as cement or plastic.

The foregoing detailed description is to be clearly understood as given by way of illustration and example only, the spirit and scope of this invention being limited solely `by the appended claims.

I claim:

1. A device for positioning in a well comprising a body,

at least one resilient member on said body,

a duality of shoulder means,

said shoulder means being positioned with one adjacent either end of said resilient member, said shoulder means bei-ng movable relatively toward each other to a position of relative adjacency for compressing said resilient member therebetween and expanding said resilient member outwardly to engage an adjacent wall of a Well, means for holding said shoulder means in said position of relative adjacency,

said holding means including opposed relatively movable members,

one of said relatively movable members being in force-transmitting relationship 'with one of said shoulder means, releasable force-transmitting means intermediate said relatively movable members, and means retaining said force-transmitting means intermediate said relatively movable members,

and means for releasing said force-transmitting means from between said relatively movable members so that said holding means no longer holds said one shoulder means and said resilient member is released rom said compression.

2. A device as recited in claim 1 in which said releasable force-transmitting means comprises a quantity of particulate material, said means retaining said forcetransrnitting means includes a chamber for said particulate material, and said means for releasing said forcetransmitting means includes means for opening said chamber for discharging said particulate material therefrom.

3. A device for insertion and positioning in a well comprising a body, at least one resilient collar circumscribing said body,

a lirst shoulder means on said .body adjacent one end of said collar,

a second shoulder means on said body adjacent the opposite end of said collar,

at least one of said shoulder means being movable relative to said body from a lfirst position relatively remote from the other shoulder means to a second position relatively adjacent said other shoulder means for compressing said collar between said shoulder means and expanding said collar outwardly for engagement with an adjacent surface of a well,

means for holding said one shoulder means in said second position,

said holding means including a lockable mem-ber for assuming a fixed position,

and a compression element for transmitting compression force between said lockable member and said one shoulder means for thereby holding said one shoulder means in said second position, and release means,

said release means including means for removing from said compression element the ability to withstand substantial compressive forces thereon so that said compression element can no longer hold said one shoulder means in said second position and said compression on said collar is released.

4. A device as recited in claim 3 in which said compression element includes means defining a chamber means,

and a quantity of particulate material in said chamber means,

said chamber means including a duality of movable members,

said movable members engaging said particulate material at opposite ends of said cham `ber means for transmitting forces ybetween said duality of members through said particulate material,

said release means including means for releasing said particulate material from said chamber means.

5. A device for positioning in a well comprising a body adapted for insertion into a well,

at least one resilient member circumscribing said body,

shoulder means at either end of said resilient member,

said shoulder means being relatively movable toward each other for compressing said resilient member therebetween to expand said resilient member outwardly into engagement with the adjacent surface of a well,

means for holding said shoulder means in a position of relative adjacency for maintaining said resilient member in compressed condition,

said holding means including means defining a chamber,

and a quantity of particulate material in said chamber for transmitting force through said chamber to said shoulder means,

and means for releasing said particulate material from said chamber so that said particulate material no longer transmits -force to said shoulder means for thereby releasing said compression of said resilient member.

6. A well packer comprising an elongated tubular mandrel adapted for insertion in a well casing,

at least one annular resilient member circumscribing said mandrel,

a first member circumscribing said mandrel at one end of said resilient member and presenting a shoulder adjacent said one end of said vresilient member,

a second member circumscribing said mandrel at the opposite end of said resilient member,

one end of said second member presenting a shoulder adjacent said opposite end of said resilient member,

said first and second members being movable relative to said mandrel,

said second member having a surface remote from said shoulder thereof,

means defining a chamber with said surface in communication therewith,

a quantity of particulate material in said chamber, a third member presenting an additional surface in communication with said chamber in opposed relationship to said surface of said second member, means for moving said first and second members relatively toward each other for compressing said annular resilient member therebetween and expanding said chamber and release said particulate material and permit telescoping movement of said duality of sleeves thereby to relieve said compression on said collar.

7. A packer for a well comprising a tubular mandrel,

at least one elastomeric resilient collar circumscribing said mandrel,

a first shoulder means engaging one end of said collar,

a second shoulder means engaging the opposite end of said collar,

at least one lock means adjacent one of said shoulder means for movement outwardly into engagement with the adjacent wall of a well casing and holding said shoulder means in a fixed position relative thereto,

a duality of telescoping sleeves around said mandrel,

said sleeves presenting opposed shoulders,

an additional sleeve inwardly of said duality of sleeves closing the space inwardly of said shoulders so that said duality of sleeves and said additional sleeve define a chamber,

a quantity of particulate material in said chamber, means for exerting a force through said chamber by said particulate material for moving said shoulder means toward each other to a position of relative adjacency for compressing said collar therebetween and causing said collar to expand outwardly into engagement with a well casing,

and means for moving said additional sleeve to open said annular resilient member outwardly against an adjacent surface of a well casing,

lock means for holding said first and second members in said position of relative adj acency,

said lock means including means holding said third member in fixed position so that compression force is transmitted through said additional surface to said particulate material to said surface of said second member and to said resilient member for holding said annular resilient member compressed between said first and second members,

and means for releasing said particulate material from said chamber so that said particulate material no longer transmits force from said third member to said second member so that said resilient member is released from said compression.

8. A well packer comprising a tubular mandrel,

at least one resilient collar circumscribing said mandrel,

a first shoulder means at one end of said collar,

a second shoulder means at the opposite end of said collar,

a first lock means adjacent said first shoulder means for movement outwardly to grip a well casing,

a second lock means for movement outwardly to grip a well casing,

said second lock means being spaced beyond said opposite end of said collar,

a compression element intermediate said second lock means and said second shoulder means,

said compression element including a duality of telescoping sleeves presenting opposed spaced shoulders,

an inner sleeve defining a chamber with said telescoping sleeves;

and a quantity of particulate material in said chamber,

means operable by said mandrel for causing said second lock means to so grip an adjacent well casing and to cause said second shoulder means to move toward said first shoulder means for compressing said collar therebetween and thereby expanding said collar outwardly into engagement with said well casing, and to cause said first lock means to so grip said well casing,

whereby said collar is maintained in said compressed condition with force from said second shoulder means to said second lock means being transmitted through said compression element, means operable by said mandrel for shifting said inner sleeve relative to said telescoping sleeves for opening said chamber and discharging said particulate material therefrom thereby to release said compression on said collar,

and means operable by said mandrel for releasing said lock means. 9. A well packer comprising a tubular mandrel, at least one resilient collar circumscribing said mandrel, a first shoulder means at one end of said collar, a second shoulder means at the opposite end of said collar, a first lock means adjacent said first shoulder means for movement outwardly to grip a well casing, a second lock means for movement outwardly to grip a well casing,

said second lock means being spaced beyond said opposite end of said collar, a compression element intermediate said second lock means and said second shoulder means,

said compression element including a duality of telescoping sleeves presenting opposed spaced shoulders, .an inner sleeve defining a -chamber with said telescoping sleeves, and a quantity of particulate material in said chamber, means operable by said mandrel for causing said second lock means to so grip an adjacent well casing and to cause said second shoulder means to move toward said first shoulder means for compressing said collar therebetween and thereby expanding said collar outwardly into engagement with said well casing, and to cause said first lock means to so grip said well casing,

whereby said collar is maintained in said compressed condition with force from said second shoulder means to said second lock means being transmitted through said compression element, said mandrelincluding a section outwardly of said second shoulder means detachable from the remainder of said mandrel,

said section of said mandrel including an abutment engageable with said inner sleeve upon axial movement of said mandrel subsequent to said detachment for thereby shifting said inner sleeve upon continued axial movement of said section of said mandrel for opening the inner wall of said chamber and discharging said particulate material therefrom thereby to release said compression on said collar, and means operable by said mandrel for releasing said lock means. 10. A well packer comprising a tubular mandrel, at least one resilient collar circumscribing said mandrel, a iirst shoulder means at one end of said collar, a second shoulder means at the opposite end of said collar, a first lock means adjacent .said first shoulder means,

said first lock means including gripping means for movement outwardly for gripping a well casing, means for normally holding said first lock means in a fixed position axially of said mandrel, a second lock means for movement outwardly to grip a well casing,

said second lock means being spaced beyond said opposite end of said collar, a compression element intermediate said lock means and said second shoulder means,

said compression element including a duality of telescoping sleeves presenting opposed spaced shoulders, an inner sleeve defining a chamber with said telescoping sleeves, and a quantity of particulate material in said chamber,

means operable by said mandrel for causing said second lock means to so grip an adjacent well casing and to cause said second shoulder means to move toward said first shoulder means for compressing said collar therebetween and thereby expanding said collar outwardly into engagement with said well casing, and to cause said first lock means to so grip said well casing,

whereby said collar is maintained in said compressed condition with force from said second shoulder means to said second lock means being transmitted through said compression element, means operable by said mandrel for .shifting said inner sleeve relative to said telescoping sleeves for opening said chamber and discharging said particulate material therefrom thereby to release said compression on said collar,

means operable by said mandrel for releasing said means holding said first lock means in fixed position relative to said mandrel for thereby permitting said first lock means to move axially relative to said mandrel,

said gripping means being releasable from said well casing upon such axial movement of said first lock means,

and means operable by said mandrel for releasing said second lock means.

11. A well packer comprising an elongated tubular mandrel,

said mandrel including a first portion and a second portion threadably connected to said first portion,

at least one resilent elastomeric collar circumscribing .said second portion of said mandrel,

a first member circumscribing said second portion of said mandrel adjacent one end of said collar and presenting a shoulder adjacent said collar,

a first slip means adjacent said first member adapted for outward expansion into engagement with an adjacent surface of a well casing,

a second member circumscribing said mandrel adjacent the opposite end of said collar,

said second member having a first end portion adjacent the opposite end of said collar and a second end portion remote therefrom,

a duality of sleeves adjacent said second end portion of said second member,

said sleeves including an outer sleeve and an inner sleeve,

Said sleeves together with said second end portion of said second member defining an annular chamber with said second end portion of said second member forming a wall thereof,

one of said sleeves including a shoulder forming a wall of said chamber in spaced opposed relationship to `said second end portion of said second member,

a particulate material in said chamber,

a second slip means adjacent said one sleeve,

and drag means associated with said second slip means for frictionaly engaging the wall of a casing and providing a resistance to movement relative thereto,

said mandrel including a shoulder engaging said first slip means for exerting a force through said first slip means in response to an upward force on said mandrel for causing said first and second slip means to engage an adjacent casing wall and for causing said rst and second members to compress said collar therebetween so that said collar is expanded outwardly into sealing engagement with said well casing,

said force being transmitted from said second member through said particulate material to said one sleeve and said second slip means,

said first portion of said mandrel being adjacent said inner sleeve and including a shoulder engageable with said inner sleeve for moving said inner sleeve relative to said outer sleeve upon the unthreading of said first portion of said mandrel from said second portion thereof for thereby releasing said particulate material from said chamber and relieving the compression on said collar so that said collar no longer engages said well casing, said first portion of said mandrel further having shoulder means for releasing said second slip means,

whereby said packer is movable in a well upon such release.

12. A well packer comprising a tubular mandrel, said mandrel including a first section, a second section, and means interconnecting said first and second sections,

at least one resilient elastomeric collar circumscribing said second section of said mandrel, a first slip means on said second section of said mandrel,

a first annular member interposed between said first slip means and said collar and engaging one end of said collar,

a first sleeve means engaging the opposite end of said collar and extending therefrom to an end portion of said first sleeve means overlapping said first section of said mandrel,

an outer sleeve means having an end portion overlapping said end portion of said first sleeve means,

said outer sleeve means including an inwardly extend wall opposed to and spaced from said end portion of said first sleeve means,

an inner sleeve means circumscribing said first section of said mandrel and extending from said end portion of said first sleeve means to said wall of said outer sleeve means so that said end portion of said first sleeve means, said outer sleeve means and said inner sleeve means define an annular chamber,

-a quantity of particulate material in said chamber substantially filling the same,

a second slip means adjacent the opposite end of said outer sleeve means,

drag block means associated with said second slip means,

means detachably connecting said first section of said mandrel to said drag block means,

retaining means releasably connecting said first annular member to said mandrel to prevent relative axial movement,

said second section of said mandrel having an annular' groove therein,

a resilient split annular member in said groove,

said resilient split annular member projecting radially above said mandrel to present a shoulder in engagement with said first slip means,

and having a free position of larger diameter than said groove, said first slip means including a circumferential surface retaining said resilient split annular member in said groove,

whereby upon a subsequent upward force on said mandrel said slip means are caused to engage the adjacent wall of a well casing and said collar is compressed between said first annular member and said first sleeve so that said collar is expanded outwardly for engagement with a well casing as a result of forces transmitted from said mandrel through said shoulder of said resilient split annular member to said first slip means,

said particulate material in said chamber thereby absorbing compression forces transmitted to said collar,

said retaining means connecting said first annular member to said mandrel being -releasable in response to such force,

means releasably attaching said first slip means to said second section of said mandrel for retaining said first slip means against movement relative to said second section of said mandrel,

said releasable attaching means of said first slip means being -releasable upon the exertion of a downward force on said mandrel while said slip means so engage a well casing,

whereby said second section of said mandrel moves said resilient split annular member away from said circumferential surface of said first slip means so that said resilient split annular member leaves said annular groove and no longer presents said shoulder adjacent said first slip means, said first section of said mandrel having a shoulder engageable with said inner sleeve upon detachment of said first section of said mandrel from said second section of said mandrel and upward movement of said first section of said mandrel for thereby sliding said inner sleeve away from said opposite end of said first sleeve and dumping said particulate material from said chamber so that said particulate material no longer transmits said force and said collar is released from said compression thereof, said first section of said mandrel having an additional shoulder engageable with said second slip means for releasing the same upon further upward movement of said first section of said mandrel.

13. In a well tool having a packing means mounted around a mandrel and a member movable along said mandrel for exerting compressive force on said packing means, the combination comprising: telescoping chamber means in said member, said chamber means having walls; substantially incompressible means in said chamber means normally preventing telescoping of said chamber means; and means operated by movement of said mandrel to open a wall of said chamber means to release said substantially incompressible means so that said chamber means can telescope to release the compressive force on said packing means.

14. In a well tool having a packing means mounted around a mandrel and `an abutment member slidable on said mandrel for exerting compressive force on said packing means, the combination comprising: a sleeve member telescopically disposed on said abutment member and movable relative thereto between extended yand contracted positions; substantially incompressible means between said sleeve member and said abutment member to normally hold said sleeve member in said extended position; and means operated by movement of said -mandrel to remove said substantially incompressible means so that said sleeve member can move to said contracted position and release the compressive force on said packing means.

15. Apparatus for use in a well bore comprising: a body having a first abutment; a tubular packing member on said body with one end engaging said first abutment; a second abutment slidable on said body and engaging the other end of said packing member so that advancement of said second abutment toward said first abutment can exert compressive force on said packing member to expand it; means responsive to movement of said body relative to said first abutment for advancing said second abutment toward said first abutment including a compressive force transmitting assembly of telescoping members forming a chamber and substantially incompressible means in said chamber to prevent telescoping movement of said telescoping members; and means responsive to movement of said body for releasing said substantially incompressible means from said chamber to permit telescoping movement of said members and withdrawal of said second abutment away from said irst abutment to rele-ase the compressive force on said packing member.

16. The apparatus of claim 3 wherein said substantially incompressible means is a material having a particulate form.

17. The apparatus of claim 16 wherein said material is sand.

18. The apparatus `of claim 15 wherein said releasing means includes a shoulder on said body engageable with one of said telescoping members; said one of said telescoping members being movable to open said chamber.

19. The apparatus of claim 15 wherein said telescoping members dulinc members include an outer member movable relative to said second abutment and an inner member movable `relative to both said outer member and said second abutment, said substantially incompressible means being conned between said inner and outer members.

20. The apparatus of claim 19 wherein said releasing means includes a shoulder on said body selectively engageable with said inner member to move said inner member relative to both said outer member and said second abutment to a position for opening said chamber.

21. A well packer for anchoring and sealing engagement with a well wall comprising: an elongated body; resilient packing means on said body; normally retracted anchor means on said body expansible into anchoring engagement with the well wall; means releasably connecting said body and said anchor means to prevent expansion of said anchor means; means for effecting expansion of said -anchor means upon longitudinal movement of said body following release of said releasable means; compressive force transmitting means for effecting axial deformation of said resilient packing means and outward expansion of said packing means into sealing engagement with said well wall in response to said longitudinal movement of said body, said compressive force transmitting means including a pair of members spaced from one another; a quantity of granular material between said members; and means for dumping said granular material in response to further longitudinal movement of said body.

References Cited UNITED STATES PATENTS 2,982,358 4/1961 Brown 166-l20 3,311,171 3/1967 Castro 277-116.4

JAMES A. LEPPINK, Primary Examiner.

U.S. Cl. X.R. 

